Rubber plates have heretofore been used for a flexographic printing; in recent years, however, various photosensitive resin structures for the flexographic printing that use thermoplastic elastomers as base polymers have been proposed instead of rubber plates.
Solution developable-types, solvent developable-types, and water or aqueous developable-types of photosensitive elastomer compositions are known as materials forming these photosensitive resin structures for the flexographic printing, and various photosensitive elastomer compositions have been proposed (see, for example, Patent document 1).
With respect to technologies for the production of these photosensitive resin structures for the flexographic printing, the CTP (Computer To Plate) technology in the flexographic platemaking has been developed.
The CTP technology for flexography involves, for example, providing a layer that is ablatable by infrared radiation on a photosensitive resin composition layer, and removing the ablation layer that corresponds to a desired image by laser radiation, thereby forming a portion that transmits active light, i.e., a negative.
As such an ablation layer, a material layer that incorporates an infrared absorbing material in a predetermined binder (see, for example, Patent document 2), and a thin layer made of a metal having infrared absorption properties (see, for example, Patent document 3) are known.
Specific examples of proposed photosensitive resin structures comprising infrared ablation layers are as follows.
For example, flexographic printing plates wherein an infrared ablation layer, a barrier layer, and a photosensitive resin composition layer are laminated in sequence have been proposed (see, for example, Patent document 4).
Moreover, as water developable-types of photosensitive resin structures for the flexographic printing, those using water-insoluble polyamides or the like as infrared ablation layers have been proposed (see, for example, Patent document 5).
Furthermore, ablation layers containing polyvinyl alcohols have also been proposed (see, for example, Patent document 6).